Early exposure of 17α-ethynylestradiol and diethylstilbestrol induces morphological changes and alters ovarian steroidogenic pathway enzyme gene expression in catfish, Clarias gariepinus.

Environmental estrogens are major cause of endocrine disruption in vertebrates, including aquatic organisms. Teleosts are valuable and popular models for studying the effects of endocrine disrupting chemicals (EDCs) in the environment. In the present study, we investigated the changes caused by exposure to the synthetic estrogens 17α-ethynylestradiol (EE2 ) and diethylstilbesterol (DES) during early stages of growth and sex differentiation of air-breathing catfish, Clarias gariepinus, at the morphological, histological, and molecular levels. Catfish hatchlings, 0 day post hatch (dph) were exposed continuously to sublethal doses of EE2 (50 ng/L) and DES (10 ng/L) until 50 dph and subsequently monitored for ovarian structural changes and alteration in the gene expression of steroidogenic enzymes till adulthood. Treated fish exhibited morphological deformities such as spinal curvature, stunted growth, and yolk-sac fluid retention. In addition to ovarian atrophy, DES-treated fish showed either rudimentary or malformed ovaries. Detailed histological studies revealed precocious oocyte development as well as follicular atresia. Further, transcript levels of various steroidogenic enzyme and transcription factor genes were altered in response to EE2 and DES. Activity of the rate-limiting enzyme of estrogen biosynthesis, aromatase, in the ovary as well as the brain of treated fish was in accordance with transcript level changes. These developmental and molecular effects imparted by EE2 and DES during early life stages of catfish could demonstrate the deleterious effects of estrogen exposure and provide reliable markers for estrogenic EDCs exposure in the environment.

FTZ-F1 and FOXL2 up-regulate catfish brain aromatase gene transcription by specific binding to the promoter motifs.

Cytochrome P450 aromatase (cyp19) catalyzes the conversion of androgens into estrogens. Teleosts have distinct, ovarian specific (cyp19a1a) and brain specific (cyp19a1b) cyp19 genes. Previous studies in teleosts demonstrated regulation of cyp19a1a expression by the NR5A nuclear receptor subfamily as well as a fork head transcription factor, FOXL2. In the present study, we investigated the involvement of fushi tarazu factor 1, FTZ-F1, a NR5A subfamily member, and FOXL2 in the regulation of cyp19a1b expression in brain of the air-breathing catfish, Clarias gariepinus. Based on the synchronous expression pattern of cyp19a1b, FTZ-F1 and FOXL2 in the brain, we isolated the 5' upstream region of cyp19a1b to analyse regulatory motifs. Promoter motif analysis revealed FTZ-F1/NR5A1 and FOXL2 binding nucleotide sequences. Transient transfection studies showed that FTZ-F1 and FOXL2 together enhanced the transcriptional activity of cyp19a1b gene in mammalian cell lines. Mutation in either of their putative binding sites within the cyp19a1b promoter abolished this effect. Electrophoretic gel mobility shift experiments indicated that FTZ-F1 and FOXL2 proteins bind to the synthesized radio-labelled oligomers used as probes and mobility shifted upon addition of their respective antibodies. Chromatin immunoprecipitation assay confirmed the binding of both these transcription factors to their corresponding cis-acting elements in the upstream region of cyp19a1b. To our knowledge, this study is the first report on the transcriptional regulation of cyp19a1b by FTZ-F1 and FOXL2 in a teleost fish.

Effect of juvenile hormone analog, methoprene on H-fibroin regulation during the last instar larval development of Corcyra cephalonica.

Juvenile hormone (JH) and 20-hydroxyecdysone (20E), co-ordinately orchestrate insect growth and development. The process of silk synthesis and secretion in lepidopteran insects is known to be under hormonal control. However, the role of JH in this process has not been demonstrated hitherto. The present study is aimed to elucidate the role of JH in H-fibroin regulation in Corcyra cephalonica, a serious lepidopteran pest. Reiterated amino acid stretches and the large molecular weight of H-fibroin render its cloning and characterization cumbersome. To address this, a commercially synthesized short amino acid peptide conjugated with a carrier protein was used to generate antibodies against the N-terminal region of H-fibroin. ELISA and immunoblot experiments demonstrated the sensitivity and specificity of antibody. Further, immunohistochemical analyses revealed the antibody's cross-reactivity with H-fibroins of C. cephalonica and Bombyx mori in the silk gland lumen. Quantitative RT-PCR and Western blot analysis demonstrated the tissue-specificity and developmental expression of H-fibroin. Hormonal studies revealed that JH alone does not alter the expression of H-fibroin. However, in the presence 20E, JH reverses the declined expression caused by 20E administration to normal levels. This study provides molecular evidence for the regulation of H-fibroin by the cumulative action of JH and 20E.

Expression and immunolocalization of 20ß-hydroxysteroid dehydrogenase during testicular cycle and after hCG induction, in vivo in the catfish, Clarias gariepinus.

The maturation inducing hormone, 17α,20ß-dihydroxy-4-pregnen-3-one (17α,20ß-DP) is required for the meiotic maturation and is produced from the precursor 17α-hydroxyprogesterone by the enzyme 20ß-hydroxysteroid dehydrogenase (20ß-HSD) in several teleosts. Central role of 20ß-HSD in ovarian cycle and final oocyte maturation is well studied when compared to spermatogenesis. In the present study, we investigated the localization and expression of 20ß-HSD in testicular cycle and gonadotropin induced sperm maturation. During testicular ontogeny, 20ß-HSD expression was detectable at 50 and 100 days post-hatch (dph), while the expression was high at 150 dph. In testicular cycle, highest levels of mRNA and protein of 20ß-HSD were observed during spawning phase. Intraperitoneal injection of human chorionic gonadotropin (hCG) to prespawning catfish elevated both 20ß-HSD transcripts and protein levels when compared to saline treated controls in a time-dependent manner. Serum 17α,20ß-DP levels, measured during different phases of testicular cycle as well as following the treatment of hCG, showed a positive correlation with the expression of 20ß-HSD. Immunolocalization revealed the presence of 20ß-HSD protein predominantly in interstitial cells and spermatogonia/spermatocytes while 20ß-HSD was undetectable in haploid cells (spermatids/sperm). These results together with high expression during spawning phase of testicular cycle and after hCG treatment in the prespawning catfish suggests a pivotal role for 20ß-HSD during testicular recrudescence leading to sperm maturation. Further studies using various fish models on testicular 20ß-HSD may provide interesting details to understand its importance in teleostean spermatogenesis.

A cross sectional study on psychological impact of covid19 on post graduate doctors and Compulsory Rotatory Residential interns in COVID isolation ward of a tertiary care centre, Madurai.

BACKGROUND: COVID-19 pandemic causes major impact on economic, physical, mental well-being of people all over the world. Doctors are working in stressful, unprepared, limited resource setting, and they are under the continuous threat of getting infection. Managing mental health of these warriors is great importance. Hence the present study to estimate the psychological impact of COVID-19* and factors associated with it among doctors in tertiary care hospital, Madurai. METHODS: A Cross-sectional study was conducted during October-November 2020 using a pre-designed semi structured questionnaire and DASS-21 scale which were sent through Google form to doctors who were in their quarantine period after the COVID duty. Totally 292 responses were received. Descriptive statistics done to find frequencies and percentages. Correlation for continuous variables; Univariate and multivariate regression for categorical variables were used to predict the factors influencing the psychological impact. RESULTS: In our study, 42.1% doctors were depressed, 43.8% were stressed and 50.7% had anxiety. Depression*, anxiety*, stress* scores were positively correlated with number of COVID duties(r2 0.163,0.138,0.133), number of elderly persons(r2 0.188,0.169,0.188) in their family and negatively correlated with sleep duration(r 2-0.219,-0.281,-0.239), attitude of study participants(r2-0.319,-0.274,-0.291). Multiple logistic regression showed that disturbed sleep(odd'sratio = 3.931,2.734,3.420) and poor quality of sleep which affect the next day function(odd'sratio = 3.470,2.968,3.122) were significant predictors for all three psychological impacts. CONCLUSION: High prevalence of psychological impact estimated, ensures the requirement of early screening with timely psychological intervention and establishment of guideline policies to support mental health of healthcare workers* for maintaining the functionality of healthcare system.

Cloning and differential expression of FOXL2 during ovarian development and recrudescence of the catfish, Clarias gariepinus.

FOXL2 is a member of the forkhead/HNF-3-related family of transcription factors which provides tissue-specific gene regulation. It is known to regulate ovarian aromatase, (cyp19a1a) which plays a crucial role in ovarian differentiation. To understand the role of FOXL2 in gonads and brain during ovarian development and recrudescence, we cloned the full-length cDNA of FOXL2 and analyzed its spatio-temporal expression both at transcript and protein levels in the air-breathing catfish, Clarias gariepinus. Based on its deduced amino acid sequence, an antigenic peptide conjugated with a carrier protein was synthesized which was then used for raising antibody that reacted specifically with FOXL2. Tissue distribution pattern of FOXL2 revealed its presence prominently in ovary and female brain with sexual dimorphism. Highest expression of FOXL2 was observed in ovary and brain during prespawning phase indicating an important role for this correlate in ovarian recrudescence. Human chorionic gonadotropin (hCG) treatment, in vitro and in vivo, induced FOXL2 expression in the ovary during preparatory and prespawning phases. Similar type of enhanced expression was evident in brain after hCG-induction during the prespawning phase. The ontogeny of FOXL2 showed sexual dimorphic expression pattern both in gonads and brain. Based on our previous studies, the expression pattern of FOXL2 was found to be synchronous not only with that of ovarian cyp19a1a but also with brain cyp19a1b. Present study substantiates the role of FOXL2 in the regulation of aromatase in teleosts and also designates FOXL2 as a potential ovary and brain marker during female sex development in catfish.

A cross-sectional study on COVID19 mortality among people below 30 years of age in Tamilnadu-2020.

INTRODUCTION: The COVID19 pandemic has turned out to be one of the public health* burdens in 2020. The fear of deaths due to COVID19 has surmounted even in developed countries and hasn't spared young age. This study aims in assessing the mortality due to COVID19 among patients below 30years of age in TamilNadu. METHODS: The data was collected from a publicly available secondary data source(www.stopcorona.tn.gov.in)which is an official COVID19 state dashboard. Details of the young COVID19 deaths* under 30yrs of age, their gender, symptoms, Co-morbidities, date of symptoms, date of admission, and death were collected till October 2020. A total of 158 deaths were included in the analysis. Fischer exact test and Mann Whitney U test* were used and p-value <0.05 was considered significant. RESULTS: Among the 158 COVID19 deaths under 30 years of age, the median age affected was 25 years(IQR-7) and 70.3% (n-111) had at least one co-morbidity*. The median time interval between symptom onset and hospital admission was 3 days (IQR-3) and between admission and death was 4 days(IQR-7).There was a significant association of myocarditis, refractory seizures, Central nervous system involvement as the cause of death in the age group 0-15years, compared with 16-30years(p < 0.05). The majority of deaths occurred with a late presentation, also patients with higher age were admitted after 2 days of symptoms and the results were statistically significant(p < 0.05). CONCLUSION: Understanding the age-dependent risk gradient and their trend of this new virus at young age* is essential for public health planning and prevent future deaths, future research gateways.

Cytochrome P450 aromatases: Impact on gonadal development, recrudescence and effect of hCG in the catfish, Clarias gariepinus.

Present study analyzed the importance of two forms of aromatases during ovarian development and recrudescence of north African/air-breathing catfish. We cloned both CYP19A1 (1941bp; ovarian form) and CYP19A2 (1786bp; brain form), which showed 47% homology between the two forms. Characterization of encoded proteins in non-steroidogenic COS-7 cells illustrated that both isoforms efficiently catalyzed the aromatization reaction by producing estradiol-17beta (E(2)) from testosterone. Tissue distribution pattern revealed preferential expression of CYP19A2 in brain while CYP19A1 predominated in ovary with trace amounts detected in other tissues including brain. Relative real-time PCR analysis revealed high transcript levels of both isoforms in the prespawning phase of ovarian cycle, which is in accordance with serum E(2) level. Aromatase activity in brain was comparatively lower than ovary, indicating the predominant requirement of aromatase in ovary. Ontogeny studies displayed sexual dimorphism, with early expression of CYP19A1 and CYP19A2 in ovary and brain, respectively. Phase-dependent rise of expression and enzyme activity of aromatase after hCG treatment revealed the stimulatory role of gonadotropin during preparatory and prespawning phases, preferentially to promote vitellogenesis. Lack of influence of hCG treatment during spawning phase endorses it further. A good correlation of expression, enzyme activity and serum E(2) levels suggests a crucial role of CYP19A1 during ovarian differentiation and ovarian cycle of catfish. Likewise, CYP19A2 might also be involved in these processes either indirectly or directly.

Cloning, characterization and transmission blocking potential of midgut carboxypeptidase A in Anopheles stephensi.

Transmission-blocking vaccines (TBV) interrupt malaria parasite transmission and hence form an important component for malaria eradication. Mosquito midgut exopeptidases such as aminopeptidase N & carboxypeptidase B have demonstrated TBV potential. In the present study, we cloned and characterized carboxypeptidase A (CPA) from the midgut of an important malarial vector, Anopheles stephensi. ClustalW amino acid alignment and in silico 3-dimensional structure analysis of CPA predicted the presence of active sites involved in zinc and substrate binding that are conserved among all the known mosquito species. Real-time PCR analysis demonstrated that CPA is predominantly expressed in the midgut throughout the mosquito life cycle and that this gene is significantly elevated in P. berghei-infected mosquitoes compared to uninfected blood-fed controls. The high midgut CPA activity correlated with the prominent mRNA levels observed. Peptide-based anti-CPA antibodies were raised that cross-reacted specifically to ∼48kDa and ∼37kDa bands, which correspond to zymogen and active forms of CPA. Further, the addition of CPA-directed antibodies to P. berghei-containing blood meal significantly reduced the mosquito infection rate in the test group compared to control and blocked the parasite development in the midgut. These results support further development of A. stephensi CPA as a candidate TBV.

Carbamazepine--the commonest cause of toxic epidermal necrolysis and Stevens-Johnson syndrome: a study of 7 years.

BACKGROUND: Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS) are a group of severe life threatening drug reactions. The drugs commonly implicated as the cause of these drug reactions vary depending on host factors and the prescription pattern of drugs in that particular area. AIM: The aim of the study was to find the drugs implicated as the cause of SJS/TEN in the patients admitted in the dermatology ward at the Medical College, Thrissur and to find the clinical outcome. METHODS: It was a retrospective study of 7 years from 1997 to 2004. The case records of all patients with a clinical diagnosis of TEN or SJS were studied in detail regarding the drugs implicated as the cause, the management and the clinical outcome. RESULTS: During the study period, 41 patients in the age group ranging from 12 to 72 years were treated as inpatients, of which 20 were males and 21 were females. The commonest drug implicated as the cause of SJS/TEN was carbamazepine (44%). The indication for carbamazepine was control of pain in more than 50% of the cases. Presence of a major systemic disease before the onset of SJS/TEN was associated with a bad prognosis. CONCLUSION: The increased use of carbamazepine, especially for control of pain, may be the reason for the increased incidence of SJS/TEN due to the same drug. Awareness about the drugs implicated in life threatening drug reactions will help physicians in preventing them by judicious use of the drugs.

Lip leishmaniasis.

A case of leishmaniasis of lip without any involvement of other parts of the body in a 36 year-old-male is described.

Genetic disruption of Abl nuclear import reduces renal apoptosis in a mouse model of cisplatin-induced nephrotoxicity.

DNA damage activates nuclear Abl tyrosine kinase to stimulate intrinsic apoptosis in cancer cell lines and mouse embryonic stem cells. To examine the in vivo function of nuclear Abl in apoptosis, we generated Abl-µNLS (µ, mutated in nuclear localization signals) mice. We show here that cisplatin-induced apoptosis is defective in the renal proximal tubule cells (RPTC) from the Abl(µ/µ) mice. When injected with cisplatin, we found similar levels of platinum in the Abl(+/+) and the Abl(µ/µ) kidneys, as well as similar initial inductions of p53 and PUMAα expression. However, the accumulation of p53 and PUMAα could not be sustained in the Abl(µ/µ) kidneys, leading to reductions in renal apoptosis and tubule damage. Co-treatment of cisplatin with the Abl kinase inhibitor, imatinib, reduced the accumulation of p53 and PUMAα in the Abl(+/+) but not in the Abl(µ/µ) kidneys. The residual apoptosis in the Abl(µ/µ) mice was not further reduced in the Abl(µ/µ); p53(-/-) double-mutant mice, suggesting that nuclear Abl and p53 are epistatic to each other in this apoptosis response. Although apoptosis and tubule damage were reduced, cisplatin-induced increases in phospho-Stat-1 and blood urea nitrogen were similar between the Abl(+/+) and the Abl(µ/µ) kidneys, indicating that RPTC apoptosis is not the only factor in cisplatin-induced nephrotoxicity. These results provide in vivo evidence for the pro-apoptotic function of Abl, and show that its nuclear localization and tyrosine kinase activity are both required for the sustained expression of p53 and PUMAα in cisplatin-induced renal apoptosis.

Endosulfan and flutamide, alone and in combination, target ovarian growth in juvenile catfish, Clarias batrachus.

Juvenile Catfish(es), Clarias batrachus of 50 days post hatch (dph) were exposed to endosulfan (2.5 parts per billion [ppb]) and flutamide (33 ppb), alone and in combination for 50 days to access their impact on ovarian development. The doses used in this study were nominal considering pervious reports. Sampling was done at 100 dph to perform histology and measurement of various transcripts, estradiol-17ß and aromatase activity. In general, treatments enhanced expression of ovary-specific transcription factors, steroidogenic enzymes steroidogenic acute regulatory protein and aromatases while transcripts of tryptophan hydroxylase2 (tph2) and catfish gonadotropin-releasing hormone declined in the brain of all treated groups with maximum reduction in the endosulfan group. Significant reduction of tph2 immunoreactivity in the forebrain/telencephalon-preoptic area endorsed our results. Increased number of pre-vitellogenic and less immature oocytes in the treated groups indicated hastened ovarian growth. Elevated ovarian aromatase activity and plasma estradiol-17ß levels were noticed in the treated groups with maximum being in the endosulfan group. These data together demonstrate that the exposure of endosulfan causes synchronous precocious ovarian development better than flutamide, alone or in combination. Our results suggest that both endosulfan and flutamide alter ovarian growth by triggering precocious development in catfish.

20-Hydroxyecdysone regulation of H-fibroin gene in the stored grain pest Corcyra cephalonica, during the last instar larval development.

20-Hydroxyecdysone (20E) controls molting, metamorphosis and reproduction of insects. It binds to a heterodimeric complex of ecdysone receptor (EcR) and ultraspiracle (USP), and regulates the transcription of genes containing ecdysone response elements (EcREs). However, the 20E regulation of silk fibroin genes is largely unexplored. In most lepidopteran larvae, the silk fibroin primarily consists of a large protein, heavy chain fibroin (H-fibroin) that is associated with two small proteins, L-chain fibroin and P25. In the present study, we demonstrate that 20E regulates the expression of H-fibroin gene in Corcyra cephalonica, in a dose-dependent manner during the last instar larval development. Semi-quantitative and real-time PCR studies reveal that physiological doses of 20E do not alter the normal expression, whereas higher doses cause a significant decline in the expression. Luciferase activity assays and gel shift experiments further confirm the presence of a functional EcRE in the upstream region of H-fibroin which regulates the ecdysteroid dependent transcriptional activity of fibroin gene through EcR. In vitro treatment with 20E mimicking insecticides, RH-5849 and RH-5992 decreases the expression of H-fibroin in isolated salivary glands. Insects fed with similar concentrations of these insecticides, metamorphose abnormally. Differences are also observed in the ultrastructure of the silk fibers of control and insecticide fed insects providing additional insight into the disruptive effects of these non-steroidal ecdysteroid agonists.

Dimorphic expression of various transcription factor and steroidogenic enzyme genes during gonadal ontogeny in the air-breathing catfish, Clarias gariepinus.

In the present study the expression of 13 genes known to be involved in sex differentiation and steroidogenesis in catfish was analyzed during gonadal ontogeny by quantitative real-time RT-PCR. Dmrt1 and sox9a showed exclusive expression in male gonads while ovarian aromatase (cyp19a1) and foxl2 were abundant in differentiating female gonads. Most of the genes related to steroidogenesis were expressed only after gonadal differentiation. However, genes coding for 3ß-hydroxysteroid dehydrogenase (3ß-hsd), 17α-hydroxylase/C17-20 lyase type 1 (cyp17) and steroidogenic acute regulatory protein (star) were barely detectable during gonadal differentiation. Ovarian aromatase, cyp19a1, which is responsible for estradiol-17ß biosynthesis in females, was expressed very early in the undifferentiated gonads of catfish, around 30-40 days post hatch (dph). The steroidogenic enzyme, 11ß-hydroxylase (cyp11b1) required for the production of 11-ketotestosterone (11-KT) was expressed only after differentiation of testis. These results suggest that estradiol-17ß has a critical role in ovarian differentiation, while the role of 11-KT in testicular differentiation is doubtful. In conclusion, dimorphic expression of dmrt1 and sox9a in gonads during early development is required for testicular differentiation, and sex-specific expression of cyp19a1 and foxl2 in females plays a critical role in ovarian development. Our study reveals that the critical period of gonadal differentiation in catfish starts around 30-40 dph when sex-specific genes showed differential expression.

Cloning and expression of StAR during gonadal cycle and hCG-induced oocyte maturation of air-breathing catfish, Clarias gariepinus.

Complementary DNAs encoding steroidogenic acute regulatory protein (StAR) have been isolated from different fish species, yet the relevance of StAR during gonadal cycle and more importantly in final oocyte maturation has not been assessed so far. A cDNA encoding StAR was isolated from the ovarian follicles of air-breathing catfish, Clarias gariepinus. Catfish StAR exhibited 55 to 72% identity at nucleotide level with other vertebrate orthologs. RT-PCR analysis of tissue distribution pattern demonstrated the presence of StAR mRNA in various tissues including gonads, kidney, liver, brain and intestine of catfish. Real-time RT-PCR analysis revealed high expression of StAR mRNA in the pre-spawning phase of ovary while it was low in preparatory, spawning and regressed phases. In testis, maximum expression was noticed during the preparatory phase. During human chorionic gonadotropin (hCG)-induced oocyte maturation, both in vitro and in vivo, StAR mRNA levels were augmented by 2 h and then declined gradually to reach basal levels by 12 h as that of saline-treated controls. Taken together, high level of expression during hCG-induced oocyte maturation vis-à-vis in spawning suggests a role for StAR, in addition to the steroidogenic enzyme genes in final oocyte maturation.

Comparison of Newcastle disease vaccines by serology using serum, tears and feather pulp samples.

Seroconversion of 3 lentogenic commercial Newcastle disease (ND) vaccines and experimental V4 vaccines was compared based on the haemagglutination inhibition (HI) test against ND. It was found that for primary vaccination all the vaccines produced similar response but for vaccinations V4 and LaSota were better than RDVF. Eight-five samples each of serum, tears and feather pulp were collected from respective birds and antibody assessment was done against ND by HI test. The geometric mean HI titres (GMT) of serum samples were highest followed by tears and feather pulp samples before vaccination and 3 weeks after vaccination by oculonasal route and the difference was statistically significant (p < 0.01). Three weeks after booster vaccination by oculonasal route, however, the GMT of serum samples were highest followed by feather pulp and tear samples. The ease of collection of feather pulp samples and their role in ND serology is discussed.

Toxic epidermal necrolysis--a retrospective study.

BACKGROUND: Toxic epidermal necrolysis (TEN) is a severe, idiosyncratic, exfoliative disease of the skin and mucous membranes. The treatment of this condition is controversial. High-dose corticosteroid therapy has been the most commonly advocated treatment, but, more recently, this has changed to a no-steroid protocol. These conflicting treatments prompted us to evaluate retrospectively our protocol. METHODS: The patients admitted to the hospital from 1989 to 1995 with a clinical diagnosis of TEN were included in the study. These patients were given systemic steroids, prophylactic antibiotic, and supportive measures. RESULTS: The patients belonged to both sexes with an average age of 34 years. The average area of involvement was 85.62%. All the patients made an uneventful recovery without any evidence of sepsis. CONCLUSIONS: Treatment with systemic steroids is useful in the management of TEN, and there is no need for a burn care center.